Actress Jessica Chastain is exploiting the recent tragedy in Las Vegas, where a gunman killed at least 58 and wounded another 515, to promote her movie that bombed in the box office last year.

Chastain, who played the lead role in “Miss Sloane” — an anti-Second Amendment movie which sold an average of 10 movie tickets per theatre during the first two weeks of the film’s box office debut — is apparently trying to hype up Blu-Ray sales of the failed movie with this tweet:

Welcome to America, where you'll wait 6 months for an X-ray but hey, you can buy an AR-15 in 5 minutes flat.

Chastain’s tweet, coming just days after the deadliest shooting in modern U.S. history, isn’t just tasteless and exploitative. It also reveals how little the actress understands about how guns work and how they’re regulated in the U.S.

As speculation abounded about the shooter’s suspected use of an automated rifle, many called for automatic weapons to be banned. As Sean Davis pointed out, fully automatic weapons are heavily regulated by the federal government, and it is a federal crime to own one absent a special license provided by the Bureau of Alcohol, Tobacco, Firearms and Explosives. While many commentators and lawmakers have demanded a new law to ban bump-fire stocks, such a ban wouldn’t actually prevent bump-firing itself, a technique which uses the physics of a gun’s recoil to significantly increase the speed at which an individual’s finger pulls the trigger on a semi-automatic weapon.

The fact that the shooter may have altered weapons legally available to purchase and modified them in order to use them for an evil purpose suggests that gun regulations demanded by gun controllers do little to prevent gun violence. After all, the shooter passed the very same background checks which gun controllers say would have prevented mass shootings.

Chastain is clearly entitled to her own opinion on the issue of gun control, but using an atrocity to juice sales of her failed movie is just gross.

Bre Payton is a staff writer at The Federalist. Follow her on Twitter.